added transient entities: when crossed, turns into wall tile

assets/levels/00-deadly-obstacles.lvl

@@ -4,8 +4,8 @@ Background: background-lila
                     
                     
    #######          
-   #  v  #          
    #     #          
+   #  t  #          
    #> S <#          
    #     #          
    #  ^  #          

assets/levels/01-friendly-obstacles.lvl

@@ -3,13 +3,13 @@ Background: background-lila
                     
                     
                     
-   #######          
-   #  ^  #          
-   #     #          
-   #< S >#          
-   #     #          
-   #^   v#          
-   #######          
+   #############    
+   #           #    
+   #>  S #     #    
+   #    >#    >#    
+   #<    #     #    
+   #    v#    <#    
+   #############    
                     
                     
                     

assets/loader-levels.go

@@ -30,8 +30,10 @@ type Tile struct {
 	Renderable  bool
 	Velocity    bool
 	Collectible bool
+	Transient   bool
 	Particle    int // -1=unused, 0-3 = show image of slice
-	Particles   []*ebiten.Image
+	Tiles       []*ebiten.Image
+	TileNames   []string // same thing, only the names
 	Obstacle    bool
 	Direction   int // obstacles
 }
@@ -77,6 +79,7 @@ func NewTileObstacle(class string, direction int) *Tile {
 		Renderable: true,
 		Obstacle:   true,
 		Direction:  direction,
+		Velocity:   true,
 	}
 }
 
@@ -93,7 +96,28 @@ func NewTileParticle(class []string) *Tile {
 		Solid:      false,
 		Renderable: false,
 		Particle:   0,
-		Particles:  sprites,
+		Tiles:      sprites,
+	}
+}
+
+func NewTileTranswall(class []string) *Tile {
+	sprites := []*ebiten.Image{}
+	names := []string{}
+
+	for _, sprite := range class {
+		sprites = append(sprites, Assets[sprite])
+		names = append(names, sprite)
+	}
+
+	return &Tile{
+		Id:         '*',
+		Class:      "transwall",
+		Solid:      false,
+		Renderable: true,
+		Transient:  true,
+		Tiles:      sprites,
+		Sprite:     sprites[0], // initially use the first
+		TileNames:  names,
 	}
 }
 
@@ -123,6 +147,7 @@ func InitTiles() TileRegistry {
 	return TileRegistry{
 		' ': {Id: ' ', Class: "floor", Renderable: false},
 		'#': NewTileBlock("block-grey32"),
+		'B': NewTileBlock("block-orange-32"),
 		'S': NewTilePlayer(),
 		'o': NewTileCollectible("collectible-orange"),
 		'+': NewTileObstacle("obstacle-star", config.All),
@@ -138,6 +163,7 @@ func InitTiles() TileRegistry {
 			"particle-ring-5",
 			"particle-ring-6",
 		}),
+		't': NewTileTranswall([]string{"transwall", "block-orange-32"}),
 	}
 }